Chapter 5 &

Chapter 6

Igneous, Metamorphic & Sedimentary

Section 5.1

What are Igneous Rocks?

• Compare and

contrast intrusive

and extrusive igneous

rocks.

• Describe the

composition of magma

• Discuss the factors

that affect how rocks

melt and crystallize.

Magma is a slushy mix of molten rock, gases, and mineral crystals.

Magma

Magma that flows out onto Earth's surface – lava

Lava

Rocks are formed when magma (or lava) crystallizes.

Rocks Form…

Igneous rocks can be identified by their physical properties of crystal size and texture.

Igneous Rock

Identification

Basalt – small - fine

Granite – large - course

phaneritic

aphanitic

Section 5.1 – extrusive

Titan’s Piazza

S. Hadley, MA

Basalt

– exhibiting

columnar

jointing

‘Jingle’ Stone

Different minerals melt and

crystallize at different

temperatures.

A model that illustrates the predictable patterns of mineral formation from cooling magma is Bowen's reaction series.

Bowen’s Reaction

Series

An ultramafic rock, such as dunite, has low silica content and very high iron and magnesium content.

Ultramafic

Dark-colored rock such as gabbro that is rich in iron (Fe) and magnesium (Mg) is mafic

Mafic

Medium colored rocks of intermediate

composition

Intermediate

Light-colored rock such as granite that has high silica content is felsic

Felsic

Both are groups of igneous rocks based on composition..

Felsic rocks

• are light-colored, have

high silica content, and

contain quartz and

feldspars.

Mafic rocks

• are darker-colored, have

low silica content, and

high iron and magnesium

content.

Mafic vs. Felsic

As the water content of rock increases, the melting point decreases.

Water & Melting Point

Quiz Section 5.1

What are Igneous Rocks?

1.Magma is a slushy mix of molten rock, gases,

and ___________ _____________. 2. ___________ is magma that flows out onto

Earth's surface. 3. Rocks are formed when magma (or Q2)

_____________.

4. Igneous rocks can be identified by their

physical properties of _____________ ________

and _____________.

5. A model that illustrates the predictable

patterns of mineral formation from cooling

magma is ________ _____________ ________.

6. Light-colored rock such as granite that

has high silica content is classified as

______________.

7. Rock such as gabbro that is rich in iron

(Fe) and magnesium (Mg) is classified as

______________.

8. An __________________ rock, such as dunite,

has low silica content and very high iron

and magnesium content.

9. Light-colored (Q6) is more likely to

contain the minerals ___________ and

feldspar.

10.As the water content of rock ___________,

the melting point decreases.

Quiz Section 5.1

What are Igneous Rocks?

Section 5.2

Classifying Igneous Rocks

• Classify different

types and textures of

igneous rocks.

• Recognize the effects

of cooling rates on

grain sizes of igneous

rocks.

• Describe some uses

of igneous rocks.

Igneous rocks that cool quickly on Earth’s surface are extrusive.

Extrusive

Igneous rocks that cool slowly beneath Earth’s crust are intrusive.

Intrusive

Intrusive igneous rocks form coarse-grained rocks.

Coarse-grained

A rock that has grains

of two different sizes

has a porphyritic texture.

Porphyritic Texture

Texture characterized by large, well-formed crystals surrounded by finer-

grained crystals of the same mineral – porphyritic

Igneous Intrusions

Valuable ore deposits are often associated with

igneous intrusions

A rare, ultramafic rock that might

contain diamonds is a kimberlite.

They are veins of extremely large-

grained minerals.

Kimberlites

Diamonds are sometimes

found in kimberlites.

Diamonds & Kimberlites

Igneous Rocks As

Resources

Igneous rocks are often used as

building materials because of their

strength, durability, and beauty.

WORD BANK for Igneous CMAP

Aphanitic Basalt Composition Dunite Extrusive

Felsic Gabbro Granite Intrusive Lava

Mafic Magma Phaneritic Rhyolite Ultramafic

Quiz Section 5.2 Classifying Igneous Rocks

1. Igneous rocks that cool quickly on Earth’s surface

are ___________.

2. Igneous rocks that cool slowly beneath Earth’s

crust are ___________.

3. When rocks cool slowly they form ________-grained

rocks.

4. A rock that has grains of two different sizes has a

_____________ texture.

5._____________ ______ deposits are often

associated with igneous intrusions.

Section 5.2 Classifying Igneous Rocks Quiz

(Continued)

6. Veins of extremely large-grained minerals are called ______________.

7. (Q6) are rare ultramafic rocks that may contain ____________.

8. Minerals melt and crystallize at __________________ temperatures.

9. Igneous rocks are often used as building materials because of their ___________, durability, and beauty.

10.On of the 3 minerals that precipitates out at the lowest temperature ,as seen on the Bowen’s Reaction series is _____________.

Section 6.1 Formation

of Sedimentary Rocks

•Sequence the

Formation of

Sedimentary Rocks.

•Explain the

formation and

classification of

clastic sediments.

•Describe features

of Sedimentary

Rocks.

Earth’s Surface

Much of Earth’s surface is covered

not by solid rock, but by

sediments.

Sediments

Pieces of solid material deposited

on Earth’s surface - sediment

Physical Weathering

During physical weathering, minerals

remain chemically unchanged.

Erosion

Landslides, moving water,

wind, and glaciers cause

erosion of surface

materials.

Effects of Gravity

Eroded materials are almost always

carried downhill.

Deposition Process of sediments being

laid down on the ground or

sinking to the bottom of

water - deposition

Cementation

During sedimentary rock formation,

cementation occurs after

weathering.

Lithification

Physical and chemical processes

that compact and transform

sediments into sedimentary rocks -

lithification

Bedding

The primary feature of sedimentary

rocks is horizontal layering called

bedding.

Graded Bedding

Graded bedding has the

heaviest and coarsest

material on the bottom.

Cross Bedding

Inclined sediment layers that migrate forward

across a horizontal surface - cross bedding

Cross-bedded sandstone (fossilized

sand dunes) near Kanab, Utah.

Quiz Section 6.1

Formation of Sedimentary

Rocks

1.Much of Earth’s surface is covered not by solid

rock, but by ___________.

2.Landslides, ___________ ___________, wind, and

glaciers cause erosion of surface materials.

3.Eroded materials are almost always carried

________________.

4.During _____________ weathering, minerals remain

chemically unchanged.

5.(Q1) being laid down on the ground or sinking to

the bottom of water is _____________.

6. During sedimentary rock formation, cementation

occurs ______________ weathering.

7. The physical and chemical processes that compact

and transform sediments into sedimentary rocks are

____________.

8. The primary feature of sedimentary rocks is

horizontal layering called __________________ .

9. ___________ (Q8) has the heaviest and coarsest

material on the bottom.

10. Inclined sediment layers that migrate forward across

a horizontal surface is _____________ _____________.

Quiz Section 6.1

Formation of Sedimentary Rocks

Section 6.2

Types of

Sedimentary Rocks

•Describe the types of clastic

Sedimentary Rocks.

•Explain how chemical

sedimentary rocks form.

•Describe organic

Sedimentary Rocks.

•Recognize the importance of

Sedimentary Rocks.

Clastic

Sediments

Clastic

sediment

particles have

worn surfaces

and rounded

corners.

Weathering

Weathering of rock

produces worn

surfaces and

rounded corners

that are

characteristic of

some clastic

sediment

particles.

Breccia Breccias are coarse-

grained sedimentary

rock with angular

fragments.

Saturation

When the concentration of minerals

dissolved in water reaches

saturation, crystals precipitate out

of solution.

Evaporite

Layers of

chemical

sedimentary

rocks that form

from

precipitated

minerals -

evaporite

Limestone

Organic sedimentary rock - limestone

Sedimentary Rocks

Sedimentary rocks form from rock and

mineral fragments, and metamorphic

rocks form from existing rock.

Porosity The percentage of open

spaces between mineral

grains in clastic rocks is

its porosity.

Benefit of porosity

The porosity of sandstone allows it

to hold oil, gas, and water.

Conglomerate vs. Evaporite

Conglomerates form

from deposits of loose

sediments on Earth’s

surface.

Evaporites form when

water evaporates from

mineral-rich solutions,

causing the minerals

to precipitate out of

the solutions.

Both are sedimentary rocks.

1.Sedimentary rocks form from ______ and

________ fragments.

2.________________ sediment particles have

worn surfaces and rounded corners.

3.________________ of rock produces worn

surfaces and rounded corners that are

characteristic of some (Q2) sediment

particles.

4._____________ is coarse-grained sedimentary

rock with angular fragments.

5.When the concentration of minerals dissolved

in water reaches _____________, crystals

precipitate out of solution.

Quiz Section 6.2

Types of Sedimentary Rocks

6.Layers of chemical sedimentary rocks that

form from precipitated minerals is a(n)

______________ .

7. One example of organic sedimentary rock is

____________ .

8. The __________________ of sandstone allows

it to hold oil, gas, and water.

9.__________________ form from deposits of

loose sediments on Earth’s surface.

10.Again, the primary feature of any

sedimentary rocks is horizontal layering

called _____________.

Quiz Section 6.2

Types of Sedimentary Rocks

Section 6.3

Metamorphic Rocks

•Compare and contrast the

different types and causes

of metamorphism.

•Distinguish among

metamorphic textures.

•Explain how mineral and

compositional changes

occur during regional

metamorphism.

•Understand how rocks

change from one type to

another in the rock cycle.

Contact Metamorphism

Contact metamorphism results when

rocks come in contact with molten rocks

such as those in an igneous intrusion.

Hydrothermal Metamorphism

Results when hydrothermal fluid

reacts with rock to change its

mineralogy, texture, and

chemistry.

Regional

Metamorphism

High temperature and pressure

which affect a large region of

the Earth’s crust – (type most

commonly seen in NE)

Foliated

Composed of minerals with crystals

that have their long axes

perpendicular to pressure - foliated

metamorphic rock

foliated, non-foliated

Both are textures of metamorphic rocks

classified by mineral grain alignment.

Foliated rocks have

distinct banding or

layers that formed

perpendicular to

pressure.

Non-foliated rocks are

crystals with blocky

shapes and do not

have banding.

Marble

The metamorphism of limestone

results in the formation of marble.

Rock Cycle

The continuous changing and reforming of rocks

is called the rock cycle.

In the Rock Cycle any rock type may

be transformed

into any other

rock type.

(copy the above illustration and information )

The Rock Cycle is the sum total of all the geologic

processes of change occurring within and upon the

Earth's lithosphere. In the rock cycle, rocks are formed,

weathered, eroded, deposited, reformed and uplifted.

Source: http://www.vtaide.com/png/rockCycle.htm

The Rock Cycle

CMAP

Igneous

Rocks

Magma/

Lava

Crystallization

Metamorphic

Rocks

Melting

Heat & Pressure

UPLIFT Sedimentary

Rocks

Sediments

Lithification &

Cementation

Rock Cycle HW

http://www.learner.org/interactives/rockcycle/testskills.html

1. ______________ metamorphism results when

rocks come in contact with molten rocks.

2. ________________ metamorphism is the type

most commonly seen in New England.

3. ________________ metamorphism results when

hydrothermal fluid reacts with rock to

change its mineralogy, texture, and

chemistry.

4. Foliated metamorphic rocks are composed of

minerals with crystals that have their

_________ _______ perpendicular to

pressure.

5. Foliated rocks have distinct _____________

or layers.

Quiz Section 6.3

Metamorphic Rocks

6. The metamorphism of limestone results in

the formation of ______________.

7. The continuous changing and reforming of

rocks is called the ________ __________ .

8. In (Q7), _______ rock type may be

transformed into ______ other rock type.

9. Rocks generally need to undergo ___________

before being weathered and eroded into

sediment.

10. Any of the rock types may undergo

_______________ to be transformed into

magma.

Quiz Section 6.3

Metamorphic Rocks